Samples of volcanic ash obtained from the Mount Schank area were tested to find if they would act as a satisfactory, naturally occurring raw material substitute for artificial fly ash presently used as a low cost ingredient in concrete mixes, that is added in to confer increased strength to the set concrete. Trial batches of Normal Portland cement were made with a proportional replacement of the company's proprietary product cement fines (i.e. Adelaide, Brighton, Geelong plant products) by pozzolanic volcanic ash. The initial trials showed that inclusion of the ground volcanic ash appeared to have little or no effect on the strength of the mixes. Thus it was deduced that the pozzolanic properties of the ash are not effective at the degree of fineness used, i.e. approx. 3500 square cm per gram. Subsequently fresh trials were conducted using volcanic ash ground to a fineness of 6950 square cm per gram, that was replaced for cement in mortar mixes in quantities of up to 15%, 20% and 25%. The resulting dried concrete batches were tested for strength after periods of 7 days and 28 days. The results indicated that an ash replacement of 5% gives the required strength in concrete, while adding a higher ash content gives correspondingly lower strengths. Further tests are still being conducted using differently sourced volcanic ash samples.